Video Experimental Relacionado
Updated: Jun 25, 2026
06:46
Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
La conversión directa de los alcoholes en acetales y H ((2) catalizada por un complejo de pinzas de rutenio a base de
Chidambaram Gunanathan1, Linda J W Shimon, David Milstein
1Department of Organic Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel.
Journal of the American Chemical Society
|February 17, 2009
Resumen
Este estudio muestra un complejo de rutenio que convierte eficientemente los alcoholes primarios en acetales y ésteres. El catalizador facilita estas transformaciones en condiciones neutrales y básicas, respectivamente, con la liberación de gas hidrógeno.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La catálisis es la catálisis.
- Síntesis orgánica La síntesis orgánica.
Sus antecedentes:
- Los complejos de rutenio son catalizadores versátiles en las transformaciones orgánicas.
- Los ligandos basados en acridina ofrecen propiedades estéricas y electrónicas únicas para la catálisis.
- La síntesis eficiente de acetalos y ésteres de los alcoholes es crucial en la química orgánica.
Objetivo del estudio:
- Para investigar la actividad catalítica de un nuevo complejo de rutenio que contiene una fracción no plana de acridina.
- Explorar la capacidad del complejo para catalizar las transformaciones del alcohol en diferentes condiciones.
- Para aclarar el mecanismo de la formación de acetal.
Principales métodos:
- Caracterización cristalográfica del complejo de rutenio RuHCl (((A- ((i) Pr-PNP) ((CO)).
- Reacciones catalíticas que involucran alcoholes primarios en medio neutro y básico.
- Análisis de los productos de reacción y subproductos, incluida la liberación de H2O.
Principales resultados:
- El complejo de rutenio cataliza de manera eficiente la formación de acetalos a partir de los alcoholes primarios en un medio neutro, liberando H(2).
- En presencia de una base, el complejo promueve el acoplamiento deshidrogenativo de los alcoholes para producir ésteres.
- La formación de acetalo probablemente se produce a través de la deshidratación hemiacetal y la posterior adición de alcohol.
Conclusiones:
- El complejo de rutenio caracterizado es un catalizador eficaz para la funcionalización del alcohol.
- La actividad del catalizador es ajustable en función de las condiciones de reacción (neutral vs. básica).
- Los hallazgos proporcionan información sobre los mecanismos de formación de acetal catalítico.
Videos de Conceptos Relacionados
01:19Aldehydes and Ketones with Alcohols: Hemiacetal Formation
Similar to water, alcohols can add to the carbonyl carbon of the aldehydes and ketones. The addition of one molecule of alcohol to the carbonyl compound forms the hemiacetal or half acetal. As depicted below, in a hemiacetal, the carbon is directly linked to an OH and OR group.
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
02:48Conversion of Alcohols to Alkyl Halides
This lesson delves into the conversion of alcohols to corresponding alkyl halides and the mechanism of action for different reagents. Typically, the hydroxyl group is first protonated to convert it to a stable leaving group. Consequently, based on the starting alcohol, the mechanism undergoes either of the nucleophilic substitution routes, SN1 or SN2. Tertiary alkyl halides are made using the two-step SN1 mechanism that occurs via a carbocation intermediate, which is stabilized by...
01:12Acid Halides to Esters: Alcoholysis
Alcoholysis is a nucleophilic acyl substitution reaction in which an alcohol functions as a nucleophile. Acid halides react with alcohol to produce esters. The mechanism proceeds in three steps:
02:15Preparation of Alcohols via Addition Reactions
Overview
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
The acid-catalyzed addition of water to the double bond of alkenes is a large-scale industrial method used to synthesize low-molecular-weight alcohols. An acidic atmosphere is required to allow the hydrogen in the water molecule to act as an electrophile and attack the double bond in an alkene. The addition of a proton to the double bond creates a carbocation intermediate. The proton preferentially bonds to the less substituted end of the double bond to create a more stable carbocation...
01:33Preparation of Aldehydes and Ketones from Alcohols, Alkenes, and Alkynes
Aldehydes and ketones are prepared from alcohols, alkenes, and alkynes via different reaction pathways. Alcohols are the most commonly used substrates for synthesizing aldehydes and ketones. The conversion of alcohol to aldehyde, which involves the oxidation process, depends on the class of the alcohol used and the strength of the oxidizing agent. For instance, primary alcohol will form an aldehyde when treated with a weak oxidizing agent; however, it gets over-oxidized to a carboxylic acid in...